Manual valve operator with override clutch apparatus

ABSTRACT

A manual valve operator with override clutch apparatus is disclosed for selectively actuating a valve. The apparatus includes an operator housing defining an enclosure. An input shaft is rotatably supported by the housing and a worm wheel has a first and a second side, the second side of the worm wheel defining a clutch drive. The worm wheel is disposed within the housing and intermeshes with the input shaft such that when the input shaft is driven, the input shaft drives the worm wheel and the clutch drive about a rotational axis. A sleeve has an outer surface which defines an annular groove. The sleeve has a driven end and an output end. The driven end of the sleeve cooperates with the clutch drive of the worm wheel for selective engagement of the clutch drive and the driven end of the sleeve. A clutch actuating handle is rotatably supported by the housing. The clutch actuating handle has a first and a second end. The second end of the clutch actuating handle defines an offset clutch driver which slidably cooperates with the annular groove of the sleeve. The arrangement is such that when the handle is rotated relative to the housing, the offset clutch driver rides within the annular groove for urging the sleeve axially along the rotational axis so that in a first axial disposition of the sleeve, the clutch drive of the worm wheel and the driven end of the sleeve are engaged relative to each other so that the sleeve is rotated by the worm wheel about the rotational axis. However, when the sleeve is disposed in a second axial disposition thereof, the driven end of the sleeve is disengaged relative to the clutch drive of the worm wheel. A driven shaft has a first and a second end, the second end of the driven shaft being connected to the valve. The driven shaft extends coaxially through the sleeve, the driven shaft being keyed to the sleeve such that relative rotation between the sleeve and the driven shaft is inhibited while axial movement of the sleeve relative to the driven shaft is permitted. The arrangement is structured such that when the sleeve is in the first axial disposition thereof, the worm wheel drivably rotates the sleeve so that the rotating sleeve rotatably drives the driven shaft for actuating the valve. Also, when the sleeve is in the second axial disposition thereof, the driven end of the sleeve is disengaged from the clutch drive of the worm wheel so that rotation of the sleeve and the driven shaft keyed thereto by the input shaft is inhibited.

BACKGROUND OF THE INVENTION FIELD OF THE INVENTION

The present invention relates to a manual valve operator with overrideclutch apparatus.

More specifically, the present invention relates to a manual valveoperator with override clutch apparatus for manually actuating a valvein the event of power source failure to a primary automated valveactuator.

BACKGROUND INFORMATION

Pneumatic pipelines and the like include quarter-turn control valvessuch as ball, plug or butterfly valves spaced along the length of theline. Such valves are relatively massive and include a flow restrictingdevice supported within the valve housing for rotation about a diametricaxis of the valve. When the valve is in a closed disposition forinterrupting the pneumatic line, the periphery of the flow restrictingdevice cooperates with a corresponding valve seating defined by thevalve housing. However, when the valve is moved to an open dispositionthereof, torque is applied to the stem of the valve by a driven shaftwhich is anchored to the flow restricting device, the driven shaftrotating about the diametric axis of the valve.

An automated valve actuator is the primary source for driving the drivenshaft for moving the flow restricting device of the valve between theopen and closed dispositions thereof. However, in the event of powersource loss to the automated valve actuator, the driven shaft can nolonger be driven. Accordingly, according to the present invention, amanual valve operator with override is able to be clutched intoengagement with the driven shaft to drive the driven shaft for turningthe flow restricting device of the valve.

According to the present invention, the manual valve operator withoverride clutch includes an input shaft with a gear which intermesheswith a worm wheel so that rotation of the input shaft causes rotation ofthe worm wheel. In turn, the worm wheel drives the driven shaft formoving the valve between the open and closed dispositions thereof.

The present invention overcomes the problem caused by a power sourceloss to the primary valve actuator by permitting selective engagement ofthe manual valve operator with override clutch apparatus for driving thedriven shaft of the valve thus facilitating operation of the valve.

Thus the primary feature of the present invention is to provide a manualvalve operator with override clutch apparatus that enables manualoperation of the valve.

Another important feature of the present invention is to provide amanual valve operator with override clutch apparatus that prevents anyback pressure from a valve being transmitted to an input shaft of themanual valve operator when disengaged.

A further important feature of the present invention, is the provisionof a manual valve operator with override clutch apparatus that providesa visual indication of the rotational disposition of the worm wheelrelative to the operator housing.

Other features and advantages of the present invention will be readilyapparent to those skilled in the art by a consideration of the detaileddescription of a preferred embodiment of the present invention containedherein.

SUMMARY OF THE INVENTION

The present invention relates to a manual valve operator with overrideclutch apparatus for selectively actuating a valve. The apparatusincludes an operator housing defining an enclosure. An input shaft isrotatably supported by the housing and a worm wheel has a first and asecond side, the second side of the worm wheel defining a clutch drive.The worm wheel is disposed within the housing and intermeshes with theinput shaft such that when the input shaft is driven, the input shaftdrives the worm wheel and the clutch drive about a rotational axis.

A sleeve has an outer surface which defines an annular groove. Thesleeve has a driven end and an output end. The driven end of the sleevecooperates with the clutch drive of the worm wheel for selectiveengagement of the clutch drive and the driven end of the sleeve. Aclutch actuating handle is rotatably supported by the housing. Theclutch actuating handle has a first and a second end. The second end ofthe clutch actuating handle defines an offset clutch driver whichslidably cooperates with the annular groove of the sleeve. Thearrangement is such that when the handle is rotated relative to thehousing, the offset clutch driver rides within the annular groove forurging the sleeve axially along the rotational axis. Thus, in a firstaxial disposition of the sleeve, the clutch drive of the worm wheel andthe driven end of the sleeve are engaged relative to each other so thatthe sleeve is rotated by the worm wheel about the rotational axis.However, when the sleeve is disposed in a second axial dispositionthereof, the driven end of the sleeve is disengaged relative to theclutch drive of the worm wheel.

A driven shaft has a first and a second end, the second end of thedriven shaft being secured to the valve. The driven shaft extendscoaxially through the sleeve, the driven shaft being keyed to the sleevesuch that relative rotation between the sleeve and the driven shaft isinhibited while axial movement of the sleeve relative to the drivenshaft is permitted. The arrangement is structured such that when thesleeve is in the first axial disposition thereof, the worm wheeldrivably rotates the sleeve so that the rotating sleeve rotatably drivesthe driven shaft for actuating the valve. Also, when the sleeve is inthe second axial disposition thereof, the driven end of the sleeve isdisengaged from the clutch drive of the worm wheel so that rotation ofthe sleeve and the driven shaft keyed thereto is inhibited.

In a more specific embodiment of the present invention, the input shaftdefines a gear.

Moreover, the worm wheel defines gear teeth which intermesh with thegear of the input shaft so that when the input shaft is driven, the wormwheel is driven about the rotational axis.

Furthermore, the clutch drive includes a plurality of clutch teeth suchthat when the worm wheel is rotated by the input shaft, the plurality ofclutch teeth rotate about the rotational axis.

Also, the sleeve is selectively rotated by the clutch drive about therotational axis and the outer surface of the sleeve is of cylindricalconfiguration.

Additionally, the annular groove is coaxial relative to the rotationalaxis.

Further, the driven end of the sleeve defines a further plurality ofclutch teeth, the further plurality of clutch teeth of the sleeve beingdriven by the plurality of clutch teeth of the worm wheel when thesleeve is disposed in the engaged first axial disposition thereof.

More particularly, the clutch actuating handle is of cylindricalconfiguration, the first end of the clutch actuating handle defining aknurled surface for facilitating rotation of the clutch actuating handleby an operator thereof.

Also, the offset clutch driver includes a roller which extends from thesecond end of the clutch actuating handle.

More specifically, the clutch actuating handle includes a portion ofcylindrical configuration, the portion being supported for rotationwithin a bore defined by the operator housing. The bore has an axiswhich is disposed normal to the rotational axis.

Additionally, the offset clutch driver extends from the cylindricalportion, the offset clutch driver being of cylindrical configuration.The offset clutch driver has a further axis which is disposed parallelto and spaced relative to the axis of the bore such that when theportion is rotated within the bore about the axis of the bore, theoffset clutch driver rides within the annular groove of the sleeve sothat regardless of a rotational disposition of the sleeve. The offsetclutch driver rides within the annular groove so that the sleeve isurged by the offset clutch driver axially along the rotational axis suchthat the sleeve is moved by the offset clutch driver between the firstand second axial dispositions of the sleeve.

Moreover, the offset clutch driver is a roller. The roller is bearinglymounted relative to the portion of the clutch actuating handle so thatthe roller rotates about the further axis.

In a preferred embodiment of the present invention, a further clutchactuating handle is disposed diametrically opposite to the clutchactuating handle relative to the sleeve.

The further clutch actuating handle includes a further portion ofcylindrical configuration. The further portion is supported for rotationwithin a further bore defined by the operator housing. The further borehas the same axis as the bore, such axis being disposed normal to therotational axis.

Additionally, a further offset clutch driver extends from the furthercylindrical portion. The further offset clutch driver is of cylindricalconfiguration and has a second axis which is disposed parallel to andspaced relative to the axis of the bores. The arrangement is such thatwhen the portions are rotated within their respective bores about theaxis of the bores, the offset clutch drivers ride within the annulargroove of the sleeve so that regardless of a rotational disposition ofthe sleeve, the offset clutch drivers ride diametrically opposite toeach other within the annular groove. The apparatus is arranged so thatthe sleeve is urged by the offset clutch drivers axially along therotational axis such that the sleeve is moved by the offset clutchdrivers between the first and second axial dispositions of the sleeve.

Furthermore, the driven shaft rotates about the rotational axis. Thedriven shaft defines a longitudinal key which extends radiallytherefrom. The longitudinal key extends between the first and secondends of the driven shaft. The longitudinal key cooperates with acorresponding longitudinal slot defined by the sleeve so that when thesleeve is in the first axial disposition thereof, the sleeve is rotatingabout the rotational axis and the cooperating longitudinal key and slotcause rotation of the driven shaft coaxially within the sleeve about therotational axis. The cooperating longitudinal key and slot also permitaxial movement of the sleeve along the driven shaft to the second axialdisposition of the sleeve so that transmission of any back pressureexerted upon the manual valve is not transmitted back to the inputshaft.

The apparatus according to the present invention also includes anindicator arm which has a proximal and a distal end. The proximal end ofthe indicator arm is secured to the second side of the worm wheel.

Also, a window is defined by the operator housing such that the distalend of the indicator arm is visible through the window for indicating arotational disposition of the worm wheel relative to the operatorhousing.

Many modifications and variations of the present invention will bereadily apparent to those skilled in the art by a consideration of thedetailed description with particular reference to the annexed drawingsthat show a preferred embodiment of the present invention. However, suchmodifications and variations fall within the spirit and scope of thepresent invention as defined by the appended claims.

Included in such modifications would be the provision of a further keyextending from the diametrically opposite side of the driven shaft, suchfurther key cooperating and sliding axially within a further slotdefined by the sleeve.

Also, the keys could be secured to the sleeve and the longitudinal slotswould in this case be defined by the driven shaft.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a manual valve operator withoverride clutch apparatus according to the present invention forselectively actuating a valve;

FIG. 2 is a similar view to that shown in FIG. 1 but shows the sleevedisposed in a second axial disposition thereof;

FIG. 3 is an enlarged view of the offset clutch driver shown in FIG. 1;

FIG. 4 is an enlarged view of the further clutch actuating handle shownin FIG. 2; and

FIG. 5 is a sectional view taken on the line 5-5 of FIG. 2.

Similar reference characters refer to similar parts throughout thevarious views of the drawings.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a manual valve operator withoverride clutch apparatus generally designated 10 according to thepresent invention for selectively actuating a valve 12. The manual valveoperator with override clutch apparatus 10 is operated when an automatedactuator generally designated 11 connected to a power source 13 becomesinoperable due to loss of power from the power source 13.

As shown in FIG. 1, the apparatus 10 includes an operator housing 14defining an enclosure 16. An input shaft 18 is rotatably supported bythe housing 14 and a worm wheel 20 has a first and a second side 22 and24 respectively. The second side 24 of the worm wheel 20 defines aclutch drive 26. The worm wheel 20 is disposed within the housing 14 andintermeshes with the input shaft 18 such that when the input shaft 18 isdriven as indicated by the arrow 28, the input shaft 18 drives the wormwheel 20 and the clutch drive 26 about a rotational axis 30.

A sleeve generally designated 32 has an outer surface 34 which definesan annular groove 36. The sleeve 32 has a driven end 38 and an outputend 40. The driven end 38 of the sleeve 32 cooperates with the clutchdrive 26 of the worm wheel 20 for the selective engagement of the clutchdrive 26 and the driven end 38 of the sleeve 32.

A clutch actuating handle generally designated 42 is rotatably supportedby the housing 14. The clutch actuating handle 42 has a first and asecond end 44 and 46 respectively. The second end 46 of the clutchactuating handle 42 defines an offset clutch driver 48 which slidablycooperates with the annular groove 36 of the sleeve 32. The arrangementis such that, when the handle 42 is rotated as indicated by the arrow 50relative to the housing 14, the offset clutch driver 48 rides within theannular groove 36 for urging the sleeve 32 axially as indicated by thearrow 52 along the rotational axis 30

FIG. 1 shows a first axial disposition of the sleeve 32. As shown inFIG. 1, the clutch drive 26 of the worm wheel 20 and the driven end 38of the sleeve 32 are engaged relative to each other so that the sleeve32 is rotated as indicated by the arrow 54 by the worm wheel 20 aboutthe rotational axis 30.

FIG. 2 is a similar view to that shown in FIG. 1 but shows the sleeve 32disposed in a second axial disposition thereof. As shown in FIG. 2, whenthe sleeve 32 is disposed in the second axial disposition thereof, thedriven end 38 of the sleeve 32 is disengaged relative to the clutchdrive 26 of the worm wheel 20.

A driven shaft generally designated 56 has a first and a second end 58and 60 respectively. The second end 60 of the driven shaft 56 is securedto the manual valve 12 by means of a further driven shaft 61 of theactuator 11. The end of the further driven shaft 61 cooperates with thesecond end 60 of the driven shaft 56 such that rotation of the drivenshaft 56 causes rotation of the further driven shaft 61. The drivenshaft 56 and further driven shaft 61 are preferably connected such thataxial movement between the shafts 56 and 61 is permitted.

The driven shaft 56 extends coaxially through the sleeve 32, the drivenshaft 56 being keyed to the sleeve 32 such that relative rotationbetween the sleeve 32 and the driven shaft 56 is inhibited while axialmovement as indicated by the arrow 52 of the sleeve 32 relative to thedriven shaft 56 is permitted. The arrangement is structured such thatwhen the sleeve 32 is in the first axial disposition thereof as shown inFIG. 1, the worm wheel 20 drivably rotates the sleeve 32 as indicated bythe arrow 54 so that the rotating sleeve 32 rotatably drives the drivenshaft 56 as indicated by the arrow 66 for actuating the valve 12 via thefurther driven shaft 61 of the actuator 11. Also, when the sleeve 32 isin the second axial disposition thereof as shown in FIG. 2, the drivenend 38 of the sleeve 32 is disengaged from the clutch drive 26 of theworm wheel 20 so that rotation of the sleeve 32 and the driven shaft 56keyed thereto is inhibited.

In a more specific embodiment of the present invention as shown in FIGS.1 and 2, the input shaft 18 defines a gear 68.

Moreover, the worm wheel 20 defines gear teeth 70 and 71 which intermeshwith the gear 68 of the input shaft 18 so that when the input shaft 18is driven as indicated by the arrow 28, the worm wheel 20 is drivenabout the rotational axis 30.

As shown in FIG. 2, the clutch drive 26 includes a plurality of clutchteeth 74, 75 and 76 such that when the worm wheel 20 is rotated by theinput shaft 18, as indicated by the arrow 54, the plurality of clutchteeth 74-76 rotate about the rotational axis 30.

Also, the sleeve 32 is selectively rotated by the clutch drive 26 aboutthe rotational axis 30 as indicated by the arrow 54.

Additionally, the outer surface 34 of the sleeve 32 is of cylindricalconfiguration and the annular groove 36 is coaxial relative to therotational axis 30.

As shown in FIG. 2, the driven end 38 of the sleeve 32 defines a furtherplurality of clutch teeth 82 and 83, the further plurality of clutchteeth 82-83 of the sleeve 32 being driven by the plurality of clutchteeth 74-76 of the worm wheel 20 when the sleeve 32 is disposed in thefirst axial disposition thereof as shown in FIG. 1.

More particularly, the clutch actuating handle 42 is of cylindricalconfiguration, the first end 44 of the clutch actuating handle 42defining a knurled surface 86 for facilitating rotation of the clutchactuating handle 42 by an operator thereof as indicated by the arrow 50.

FIG. 3 is an enlarged view of the offset clutch driver 48 shown inFIG. 1. As shown in FIG. 3, the offset clutch driver 48 includes aroller 90 which extends from the second end 46 of the clutch actuatinghandle 42.

More specifically, the clutch actuating handle 42 includes a portion 92of cylindrical configuration, the portion 92 being supported forrotation as indicated by the arrow 50 within a bore 96 defined by theoperator housing 14. The bore 96 has an axis 98 which is disposed normalto the rotational axis 30.

Additionally, the offset clutch driver 48 extends from the cylindricalportion 92, the offset clutch driver 48 being of cylindricalconfiguration. The offset clutch driver 48 has a further axis 100 whichis disposed parallel to and spaced relative to the axis 98 of the bore96 such that when the portion 92 is rotated as indicated by the arrow 50within the bore 96 about the axis 98 of the bore 96, the offset clutchdriver 48 rides within the annular groove 36 of the sleeve 32. Thearrangements is such that regardless of a rotational disposition of thesleeve 32, the offset clutch driver 48 rides within the annular groove36 so that the sleeve 32 is urged, as indicated by the arrow 52, by theoffset clutch driver 48 axially along the rotational axis 30 so that thesleeve 32 is moved as indicated by the arrow 52 by the offset clutchdriver 48 between the first and second axial dispositions of the sleeve32 as shown in FIGS. 1 and 2 respectively.

The roller 90 is bearingly mounted relative to the portion 92 of theclutch actuating handle 42 so that the roller 90 rotates as indicated bythe arrow 108 about the further axis 100.

In a preferred embodiment of the present invention, as shown in FIG. 2,a further clutch actuating handle 110 is disposed diametrically oppositeto the clutch actuating handle 42 relative to the sleeve 32.

FIG. 4 is an enlarged view of the further clutch actuating handle 110shown in FIG. 2. As shown in FIG. 4, the further clutch actuating handle110 includes a further portion 112 of cylindrical configuration. Thefurther portion 112 is supported for rotation, as indicated by the arrow114, within a further bore 116 defined by the operator housing 14. Thefurther bore 116 has the same axis 98 as the bore 96, such axis 98 beingdisposed normal to the rotational axis 30.

Additionally, a further offset clutch driver 118 extends from thefurther cylindrical portion 112. The further offset clutch driver 118 isof cylindrical configuration and has a second axis 120 which is disposedparallel to and spaced relative to the axis 98 of the bores 96 and 116.Normally, the axis 120 will be that same as the axis 100. Thearrangement is such that when the portions 92 and 112 are rotated withintheir respective bores 96 and 116 about the axis 98 of the bores 96 and116 as indicated by the arrows 50 and 114 respectively, the offsetclutch drivers 48 and 118 respectively ride within the annular groove 36of the sleeve 32 so that regardless of a rotational disposition of thesleeve 32, the offset clutch drivers 48 and 118 ride diametricallyopposite to each other within the annular groove 36. The apparatus 10 isarranged so that the sleeve 32 is urged by the offset clutch drivers 48and 118 axially along the rotational axis 30 as indicated by the arrow52 such that the sleeve 32 is moved by the offset clutch drivers 48 and118 between the first and second axial dispositions of the sleeve 32 asshown respectively in FIGS. 1 and 2.

FIG. 5 is a sectional view taken on the line 5-5 of FIG. 2. As shown inFIG. 5, the driven shaft 56 rotates about the rotational axis 30 asindicated by the arrow 66. The driven shaft 56 defines a longitudinalkey 130 which extends radially from the driven shaft 56. Thelongitudinal key 130 extends between the first and second ends 58 and 60respectively of the driven shaft 56. The longitudinal key 130 cooperateswith a corresponding longitudinal slot 132 defined by the sleeve 32 sothat when the sleeve 32 is in the first axial disposition thereof asshown in FIG. 1, the sleeve 32 is rotating as indicated by the arrow 66about the rotational axis 30, and the cooperating longitudinal key 130and slot 132 cause rotation of the driven shaft 56 coaxially within thesleeve 32 about the rotational axis 30. The cooperating longitudinal key130 and slot 132 also permit axial movement as indicated by the arrow 52of the sleeve 32 along the driven shaft 56 to the second axialdisposition of the sleeve 32 as shown in FIG. 2, so that transmission ofany back pressure exerted upon the valve 12 is not transmitted back tothe input shaft 18.

As shown in FIG. 2, the apparatus 10 according to the present inventionalso includes an indicator arm 138 which has a proximal and a distal end140 and 142 respectively. The proximal end 140 of the indicator arm 138is secured to the second side 24 of the worm wheel 20.

Also, a window 144 is defined by the operator housing 14 such that thedistal end 142 of the indicator arm 138 is visible through the window144 for indicating a rotational disposition of the worm wheel 20relative to the operator housing 14.

In operation of the manual valve operator with override clutch apparatusaccording to the present invention, in the event of a power failure, theinput shaft 18 is manually rotated as indicated by the arrow 28, so thatthe gear 68 drives the worm wheel 20. Accordingly, the worm wheel 20rotates about the rotational axis 30. Consequently, the clutch teeth74-76 of the worm wheel 20 drive the sleeve 32 when the sleeve is in thefirst disposition thereof as shown in FIG. 1. Because the sleeve 32 isconnected to the driven shaft 56 by the interaction of the key 130 andthe slot 132, the driven shaft 56 will drive the further driven shaft 61of the actuator 11, for manually driving the valve 12 between an openand a closed disposition thereof.

Those skilled in the art will appreciate that when the valve 12 isdisposed in a pneumatic line or the like, considerable torque is exertedon the valve 12 by for example the pneumatic pressure of the line. Suchtorque is transmitted back through the further driven shaft 61 to thedriven shaft 56. Consequently, when the automated valve actuator losespower for any reason, it is very important to control such back torqueapplied through the driven shaft. The present invention enables anoperator to manually rotate the clutch actuating handles 42 and 110 sothat the sleeve 32 is urged from the second disposition thereof as shownin FIG. 2 to the engaged first disposition of the sleeve 32 so thatrotation of the driven shaft 56 is controlled from the worm wheel 20.Thus, in the engaged first disposition of the sleeve 32, as shown inFIG. 1, the worm wheel 20 including the operator housing 14 can be usedto control the valve 12 by overcoming the torque by engaging the wormwheel 20 and input shaft 18.

The present invention provides a unique manual valve operator withoverride clutch apparatus that greatly facilitates engagement anddisengagement of the manual valve operator from the valve.

1-17. (canceled)
 18. A manual override clutch assembly comprising: aworm wheel having a side, a rotational axis, and a first plurality ofclutch teeth extending outward from said side; a sleeve comprising asecond plurality of clutch teeth formed complimentary to said firstplurality of clutch teeth, said sleeve further comprising an annulargroove therein that is substantially concentric with the rotationalaxis; a first clutch actuating handle rotatable about a first clutchaxis, said first clutch actuating handle comprising a first offsetclutch driver having a first longitudinal axis parallel to and spacedfrom the first clutch axis; and a second clutch actuating handlerotatable about a second clutch axis, said second clutch actuatinghandle comprising a second offset clutch driver having a secondlongitudinal axis parallel to and spaced from the second clutch axis,wherein each of said first and said second offset clutch driversslidably cooperate with said annular groove to move said sleeve betweena first position where said second plurality of clutch teeth arerotatably coupled to said first plurality of clutch teeth inform-fitting engagement, and a second position wherein said secondplurality of clutch teeth are disengaged from said first plurality ofclutch teeth.
 19. The clutch assembly in accordance with claim 18,wherein the first clutch axis is normal to and intersects the rotationalaxis of said worm wheel.
 20. The clutch assembly in accordance withclaim 18, wherein the second clutch axis is substantially collinear withthe first clutch axis.
 21. The clutch assembly in accordance with claim18, wherein each of said first and said second offset clutch driverscomprise a roller hearing coupled to said first and said second offsetclutch drivers respectively.
 22. The clutch assembly in accordance withclaim 18, further comprising an indicator arm coupled to said side ofsaid worm wheel, said indicator arm configured to indicate an amount ofrotation of said worm wheel.
 23. A valve assembly comprising: a valverotatable about a longitudinal axis; a drive shaft coupled to saidvalve, said drive shaft coaxial with the longitudinal axis; a manualvalve operator housing comprising a manual override clutch assembly,said manual override clutch assembly comprising: a worm wheel having aside, a rotational axis coaxial with the longitudinal axis of said,valve, and a first plurality of clutch teeth extending outward from saidside; a sleeve comprising a second plurality of clutch teeth formedcomplimentary to said first plurality of clutch teeth, said sleevefurther comprising an annular groove therein that is substantiallyconcentric with the rotational axis, said sleeve slidably coupled tosaid drive shaft; a first clutch actuating handle rotatable about afirst clutch axis, said first clutch actuating handle comprising a firstoffset clutch driver having a first longitudinal axis parallel to andspaced from the first clutch axis; and a second clutch actuating handlerotatable about a second clutch axis, said second clutch actuatinghandle comprising a second offset clutch driver having a secondlongitudinal axis parallel to and spaced from the second clutch axis,wherein each of said first and said second offset clutch driversslidably cooperate with said annular groove to move said sleeve betweena first position where said second plurality of clutch. teeth arerotatably coup led to said first plurality of clutch teeth inform-fitting engagement, and a second position Wherein said secondplurality of clutch teeth are disengaged from said first plurality ofclutch teeth.
 24. The valve assembly in accordance with claim 23,wherein said manual valve operator housing further comprises an inputgear drivingly coupled to said worm wheel.
 25. The valve assembly inaccordance with claim 24, wherein said input gear is a worm gear. 26.The valve assembly in accordance with claim 23, wherein said sleevefurther comprises at least one slot therein that is substantiallyparallel to the rotational axis.
 27. The valve assembly in accordancewith claim 26, wherein said drive shaft comprises at least onelongitudinal key extending radially from said drive shaft, saidlongitudinal key configured to slid ugly couple to said at least oneslot in said sleeve, wherein relative rotation between said sleeve andsaid drive shaft is substantially inhibited and relative axial movementbetween said sleeve and said drive shaft is permitted.
 28. The valveassembly in accordance with claim 23, wherein the first clutch axis isnormal to arid intersects the rotational axis of said worm wheel. 29.The valve assembly in accordance with claim 23, wherein the secondclutch axis is substantially collinear with the first clutch axis. 30.The valve assembly in accordance with claim 23, wherein said firstclutch actuating handle and said second clutch actuating handle are eachrotatably coupled to said housing, said first clutch actuating handleand said second clutch actuating handle positioned diametricallyopposite each other relative to said sleeve.
 31. The valve assembly inaccordance with claim 23, wherein each of said first and said secondoffset clutch drivers comprise a roller bearing coupled to said firstand said second offset clutch drivers respectively.
 32. The valveassembly in accordance with claim 23, wherein said manual overrideclutch assembly further comprises an indicator arm coupled to said sideof said worm wheel, said indicator arm configured to indicate an amountof rotation of said worm wheel.
 33. The valve assembly in accordancewith claim 32, wherein said manual valve operator housing furthercomprises a window therein, wherein an end of said indicator arm isvisible through said window for indicating the amount of rotation ofsaid worm wheel.
 34. A method of assembling a manual override clutchassembly for a valve assembly, the method comprising: providing a manualvalve operator housing; rotatable coupling a worm wheel within themanual valve operator housing, the worm wheel including a rotationalaxis and a first plurality of clutch teeth extending outward from a sideof the worm wheel; slidably coupling a sleeve within the manual valveoperator housing, the sleeve including a second plurality of clutchteeth formed complimentary to the first plurality of clutch teeth, thesleeve further including an annular groove therein that is substantiallyconcentric with the rotational axis of the worm wheel; rotatablecoupling a first clutch actuating handle to the manual valve operatorhousing, the first clutch actuating handle having a first clutch axisand a first offset clutch driver, the first offset clutch driver havinga first longitudinal axis parallel to and spaced from the first clutchaxis; and rototably coupling a second clutch actuating handle to themanual valve operator housing, the second clutch actuating handle havinga second clutch axis and a second offset clutch driver, the secondoffset clutch driver having a second longitudinal axis parallel to andspaced from the second clutch axis, wherein each of the first and thesecond offset clutch drivers slidably cooperate with the annular grooveto move the sleeve between a that position where the second plurality ofclutch teeth are rotatably coupled to the first plurality of clutchteeth in form-fitting engagement, and a second position wherein thesecond plurality of clutch teeth are disengaged from the first pluralityof clutch teeth.
 35. The method in accordance with claim 34, furthercomprising drivingly coupling an input gear to the worm wheel.
 36. Themethod in accordance with claim 34, wherein the first clutch axis isnormal to and intersects the rotational axis of said worm wheel.
 37. Themethod in accordance with claim 34, wherein the second clutch axis issubstantially collinear with the first clutch axis.